> there is no way to stop someone coding in assembler from making a kernel system call.

Take a look at OpenBSD, then- if you make a syscall from any language at all, but it's not from within libc, the kernel will simply kill the process: https://lwn.net/Articles/806776/

This forced Go to switch from making direct syscalls to making them indirectly via libc: https://utcc.utoronto.ca/~cks/space/blog/programming/Go116Op...

I don't really care about your opinion of Rust, but if anything can make people who behave like you this upset, I'm all for it.